American charter schools have become embroiled in a proxy fight between Turkish President Recep Tayyip Erdogan and Fethullah Gulen

Lawyer Robert Amsterdam is working for the government of Turkey to investigate schools and other institutions he says are connected to Muslim cleric Fethullah Gulen, whom Turkish officials blame for July’s coup attempt. PHOTO: STEPHEN VOSS FOR THE WALL STREET JOURNAL

A global proxy war between the president of Turkey and his No. 1 nemesis played out early this year in an otherwise routine public-school board meeting in Fremont, Calif.

On the agenda during the January meeting was a pitch from the chief executive of a California charter-school chain, which had proposed opening an outpost in the Silicon Valley suburb.

Also in attendance, and bearing a long list of objections, was a lawyer representing the Republic of Turkey.

The attorney, from London-based Amsterdam & Partners LLP, “has been following us around lately” trying to block the chain’s projects, Caprice Young, chief executive of Magnolia Public Schools, told the Fremont board. “He is a representative of the Turkish government who seems to believe that we are affiliated with a religious group with whom we are not affiliated.”

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Turkish president Recep Tayyip Erdogan pinned the coup attempt that gripped the country on a self-exiled cleric living in the U.S. named Fethullah Gulen. Gulen denies any involvement. Here’s a closer look at this influential preacher. Photo: AP (Originally published July 18, 2016)

Turkish officials blame Mr. Gulen for orchestrating a July 15 coup attempt. They accuse him of trying to subvert the democratically elected government via positions his sympathizers hold in the judiciary, police and academia.

Turkey has asked the U.S. to extradite Mr. Gulen on charges unrelated to the putsch. U.S. officials have said they would consider all evidence Turkey presents as part of an extradition request; privately, many senior U.S. officials said they are skeptical of Turkey’s claims against Mr. Gulen.

Mr. Gulen’s network is hard to define. His supporters run schools and foundations around the world with clear ties to him. His links to other institutions are less clear, including to U.S. schools such as Magnolia. The chain was founded by two Gulen sympathizers and counts Gulen admirers among its teachers, said its CEO, Dr. Young. She said Magnolia has no legal, financial or governance connection with him.

Robert Amsterdam, whose firm was hired by Turkey, said he has about 25 employees and consultants fanned out around the globe to prove a theory, an effort that predated the coup attempt and has gathered momentum since. Roughly 150 schools in the U.S., and hundreds of other academic institutions and businesses around the world, he claims, channel millions of dollars annually to the Gulen movement.

“This is truly a global political and criminal movement,” said Mr. Amsterdam. “In the U.S., they’re teaching 60,000 students. I don’t know how they have time to teach when they spend so much time gaming the system.”

A Turkish embassy official in Washington referred inquiries to Mr. Amsterdam.

His representatives referred inquiries to Yuksel Alp Aslandogan, executive director of the Alliance for Shared Values, a nonprofit that promotes Mr. Gulen’s ideas and his “Hizmet” movement. Mr. Gulen denies involvement in the failed coup, denies trying to subvert the government and is opposed to violence, said Mr. Aslandogan. The cleric, he said, is 77 or 78 years old.

Mr. Aslandogan defended the movement, saying: “There are hundreds of businesses and NGOs within the Hizmet movement that have been legally operating around the world…and have been praised by local authorities and heads of state for their contributions to the country in which they operate.”

Some U.S. schools on Mr. Amsterdam’s hit list were founded by Gulen sympathizers but Mr. Gulen doesn’t run them, said Mr. Aslandogan, who himself helped start a school in Chicago.

‘Money laundering’

Mr. Amsterdam is aiming to tie the schools on his list to Mr. Gulen and expose what he said is a “money laundering” scheme. Some schools, he said, illegally use public funding to pay for immigration lawyers to win visas for teachers and administrators from Turkey. The schools then expect these Turkish employees to donate to the Gulenist movement, he said, and pressure them to donate to American politicians who advocate for Mr. Gulen.

The schools, he said, illustrate why Mr. Gulen should be extradited. They “give him political influence in a very big way,” he said.

Caprice Young, CEO of Magnolia Public Schools, one target of Mr. Amsterdam’s team, says the California charter-school chain was founded by sympathizers of Mr. Gulen but has no affiliation with him. PHOTO: MICHAL CZERWONKA FOR THE WALL STREET JOURNAL